Stator of a moineau-pump

Abstract

A Moineau stator includes a tube ( 10 ) having lobes ( 3 ) arranged in a configuration which is adapted to interact with a rotor and formed through a hydroforming process.

1. A Moineau stator, comprising:
 a tube ( 10 ) having lobes ( 3 ) arranged in a configuration which is adapted to interact with a rotor, the tube ( 10 ) is thin-walled with walls ( 2 ) that are sufficiently thin as to be subjected to elastic deformation in response to interfacial seal forces imposed by interference with the rotor and is surrounded by a supporting structure ( 201 ) in the form of a support housing having walls able to resist pressure, torque, and axial loads experienced in its intended operating environment, discrete pressurized axial cavities ( 203 ) are positioned in an annulus ( 202 ) between the tube ( 10 ) and the support housing ( 201 ) and fluid passages ( 206 ) are provided to equalize pressure in the axial cavities ( 203 ) with pressure within the interior ( 5 ) of the tube ( 10 ) by allowing fluids from the interior ( 5 ) of the tube ( 10 ) to communicate with the axial cavities ( 203 ). 
 
     
     
       2. The Moineau stator as defined in  claim 1 , wherein the support housing ( 301 ) has lobes arranged in a configuration adapted to interact with the lobes on the tube ( 10 ) to form said discrete pressurized axial cavities, thereby balancing pressure acting on the interior surface ( 5 ) of the tube ( 10 ) with a substantially equal pressure acting on the exterior surface ( 6 ) of the tube ( 10 ) such that the deformation of the tube ( 10 ) in response to pressure variations is limited. 
     
     
       3. The Moineau stator as defined in  claim 2 , wherein one of an exterior surface ( 6 ) of the tube ( 10 ) or an interior surface of the support housing ( 301 ) is coated with elastomer ( 302 ).